STUDY OF THE EVALUATION METHOD FOR FLOOD DISASTER-REDUCTION MEASURES CONSIDERING EXCESSIVE FLOODS IN A FLOODPLAIN OF SMALL-MEDIUM SIZED RIVERS 2 3 2 2 4 Kenaro TAKI, Tesuhro MATSUDA, Em UKAI, Saosh FUJII, Takehko KAGEYAMA, Shn EGASHIRA 520-8577 4-- 2 53-0074 2-3-20 3 53-0074 2-3-20 4 53-0074 2-3-20 Presen paper proposes a mehod o evaluae he effecveness of several negraed counermeasures agans flood hazards wh specal aenon focused on lves of nhabans n an urbanzed area formed n an alluval flood plan. Each negraed counermeasure s consued b combnng some of a sngle measure such as a flood conrol dam, srenghenng embankmen performances, flood plan regulaon works, warnng and evacuaon ssem ec. Supposng ha floods of varous szes wh 0- o 200-ear reurn perods ake place, each of he negraed measures s appled o a arge area of Shga Prefecure o nvesgae s effecveness from a vew pon of human loss as well as of houses damages, usng he followngs: poenal human loss curves, evacuaon rang curves and smulaed ranfall runoffs, rver flows and flood flows due o bank breaches. These analses provde a ear-b-ear change of he human loss rsk correspondng o each negraed counermeasure and useful nformaon for choosng a bes measure. Ke Words : small-medum szed rvers, flood-reducon measures, ecessve floods, evaluaon mehod, horzonal wo-dmensonal unsead flow analss, epeced value of damage 20~30 ) 2) 3) - 49 -
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K 2) m m m m m m 0.53 6.3 0.75 0.036 0.005 8 0 50 00 200 4 0 50 50km 2 00 200 3.0 4) 24 6 0) 8) 200 00.2 ) K K K = H.W.L. na C / 2 (7) D g Dh dlnbranch na = (8) 2 L h C D =.2 D m d m l m n branch L 6) m h m h =Mnh, h n branch =h h V n br n branch 0 h m n br /m h V m K 2) h=3.0m 6) u 2 h=2.5m 3 /s 2 9) DID 6,000/ha 45 970 3) /2500 50mm 0 7 50mm 0.45m 3) HM 2007-5 -
- 52-60 5.0 =30 4) 20072 2,484 77% 5 5) HM HM 0% 6) HM.0 0% HM Case. Case.60 200 Case. Case.6 42 0.9 0.7 0.5 0.3 0. 5) Case. Case.2 Case.3 Case.4 Case.5 Case.6 Case.5 Case. Case.2 Case.4 Case.5
Case.3 3m 2.5m 3 /s 2 Case. 0 200 3m Case. 6.9/ Case. 2Case.342.0/ Case.6 0 200 /0 /50 /00 /200 Case. 3.2 72.7 29.3 294.5 6.8 HM Case. 6.8 5.60 HM 4.66 0.25 0.22 HM 0.20 HM Case.2 0.0 65.4 7.7 43. 4.56 Case.3 3.2 6. 76. 2 230.8 2.40 Case.4 3.2 62.5 85.6 253.0 5.37 Case.5 3.2 5.0 22. 282.4 2.07 Case.6 0.0 0.5 4.6 40.2 0.25 Case.6 /0 /50 /00 /200 Case.,042 3,00 4,58 6,04 230.7 Case.2 62,844 2,779 4,40 2.3 Case.3 569 3,048 4,249 5,582 205.7 Case.4,033 3,00 4,32 6,23 224. Case.5,042 3,24 4,623 5,88 235.7 Case.6 49,344 2,359 4,66 94.5 59 3m2.5m 3 /s 2 Case. Case.6 26 38253 0 / 5 / Case.2 Case.4 Case.2Case.3 Cas Cas e.3 e.2case.3case.4 0.4-53 -
) 06 pp.63-8596. 2) BVol.64 No.pp.-22008. 3) 2005. 4) 200. 5) 23 B-2pp.305-37 980. 6) 3400 996. 7) 9 2003.6 8) 7 507-4 pp.5-252007. 9) 860 33 pp.33-336989 0) 2008. ) 3538 998. 2) 3 2002. 3) 970. 4) Vol.37CD-ROM(272)2008. 5) pp.2-7995. 6) 0 8 pp.3-4999. - 54 -